Question

A wheel barrow is used to lift a 150 lb load. The length from the wheel axle to the center of the load is 2 ft. The length from the wheel and axle to the effort is 6 ft. a. What is the ideal mechanical advantage of the system? b. Using static equilibrium calculations, calculate the effort force needed to overcome the resistance force in the system.

Answer 1

`3:1`

`50\ \text{lb}`

Step-by-step explanation:

`F_r=150\ \text{lb}`

Mechanical advantage is will be the ratio of the distances from the wheel axle of the forces.

`MA=(6)/(2)\\\Rightarrow MA=3:1`

The ideal mechanical advantage of the system is
`3:1`.

The moment in the system is conserved so moment about the wheel axle is

`M_e=M_r\\\Rightarrow 6F_e=2F_r\\\Rightarrow F_e=(2F_r)/(6)\\\Rightarrow F_e=(2* 150)/(6)\\\Rightarrow F_e=50\ \text{lb}`

The required effort force is
`50\ \text{lb}`.